wp-bootstrap/src/scss/rtl.scss

/*!
 * WP Bootstrap Theme - RTL Overrides
 * Right-to-left language support
 */

// Blockquote accent border (LTR uses border-left, RTL needs border-right)
.is-style-blockquote-accent {
    border-left: none;
    border-right: 4px solid var(--wp--preset--color--primary);
    border-radius: 0.375rem 0 0 0.375rem;
}